R&D: Near Infrared Persistent Luminescence of Transparent Zn-Ga-Ge-O:Cr3+ Glass Ceramic for Optical Information Storage

Ceramics International has published an article written by Zhiyuan Liu, Bo Wang, Kang Zhang, Tianpeng Liu, School of Applied Physics and Materials, Wuyi University, Jiangmen, Guangdong, 529020, PR China, Rui Zhang, Ministry-Province Jointly-Constructed Cultivation Base for State Key Laboratory of Processing for Non-ferrous Metal and Featured Materials, Guangxi Key Laboratory of Optical and Electronic Materials and Devices, College of Materials Science and Engineering, Guilin University of Technology, Guilin, 541004, PR China, and Qingguang Zeng, School of Applied Physics and Materials, Wuyi University, Jiangmen, Guangdong, 529020, PR China.

Abstract: “Cr³⁺-doped near-infrared (NIR) afterglow phosphors have received wide recognition in the optical storage field because of the high signal-to-noise ratio and broad excitation spectra. In this article, the high-temperature TL intensity of ZnGa₂O₄:Cr³⁺ afterglow glass ceramic (ZGO:Cr³⁺ GC) was enhanced via partial hetero-valence substitution of Ge for Ga, demonstrating the tunability of the trapped electron levels in ZGO:Cr³⁺ GC. The persistent luminescence phosphor ZGO:Cr³⁺ GC exhibits a zero-phonon lines emission peaking at 698 nm, attributing to the ²E→⁴A_2g transition of Cr³⁺ ions. Moreover, the trap levels in Zn-Ga-Ge-O:Cr³⁺ glass ceramic (ZGGO:Cr³⁺ GC) are deeper than those of the Ge-free one and the captured electrons in deeper levels cannot be released only by the ambient thermal energy, thus the optical storage capacity of ZGGO:Cr³⁺ GC is much larger. By means of an additional 980nm laser photostimulation, an intense NIR emission could be obtained. In consequence, ZGGO:Cr³⁺ GC has a promising application prospect in optical information storage field.“